Power train or transmission

Abstract

A power train infinitely variable from substantially 1:1 ratio to a very high ratio, employing a pair of planetary gear assemblies, each including a sun gear, a ring gear and a planetary carrier having at least one planetary gear operatively connecting the associated ring and sun gears, the planetary gear assemblies having different gear ratios, both planetary assemblies having their sun gears rotatable by a driving member, a driven member operatively connected to the planetary carrier of the assembly of higher ratio, the ring gears being constructed for rotation as a unit, and the planetary carrier of the assembly of lower ratio being variably connectible with the driving member, whereby the overall ratio between driving and driven members is variable in dependence upon the relative speed of the driving member and the planetary carrier of the lower ratio assembly.

I claim: 
     
       1. A power train variable from substantially a 1:1 ratio to a higher ratio, comprising a driving member and a driven member, a pair of planetary gear assemblies, each including a sun gear, a ring gear and a planetary carrier having at least one planetary gear operatively connecting the associated ring and sun gears, said gear assemblies having different gear ratios, both planetary assemblies having their sun gears rotatable by said driving member, said driven member being operatively connected to the planetary carrier of one of said assemblies, means connecting said ring gears for rotation as a unit, and means for selectively rotating the planetary carrier of the other of said assemblies at desired speeds with respect to the driving member, whereby the overall ratio between the driving and driven members is variable in dependence upon the relative speeds of said driving member and said planetary carrier of said other of said assemblies. 
     
     
       2. A power train according to claim 1, wherein said driven member is connected to the planetary carrier of the assembly of higher ratio, and the planetary carrier of the assembly of lower ratio is selectively rotatable by said planetary carrier rotating means, with the overall ration between the driving and driven members being variable in dependence upon the relative speeds of said driving member and said planetary carrier of the lower ratio assembly. 
     
     
       3. A power train according to claim 2, wherein said drive shaft is connected to one rotative source, and said means for rotating said planetary carrier of the lower ratio assembly comprises a second rotative source. 
     
     
       4. A power train according to claim 2, wherein independently operable reversing gears are provided at the driven member for reversing rotation thereof with respect to the rotation of the associated planetary carrier. 
     
     
       5. A power train according to claim 2, wherein said means for rotating said planetary carrier of the lower ratio assembly comprises means selectively connecting said assembly to the driving member. 
     
     
       6. A power train according to claim 5, wherein said means selectively connecting said planetary carrier and the driving member comprises a fluid coupling having a driving element connectible to said driving member and a driven element connectible to said planetary carrier. 
     
     
       7. A power train according to claim 5, wherein said means selectively connecting said planetary carrier and the driving member comprises a magenetic clutch having a driving element, a driven element and means for effecting a variable coupling between said elements, the driving elements being connected to said driving member and the driven element to said planetary carrier. 
     
     
       8. A power train according to claim 5, wherein said ring gears are rigidly connected, means for selectively connecting and disconnecting said variable connecting means and said planetary carrier of the assembly of lower ratio, means for selectively maintaining the last-mentioned planetary carrier stationary, and means for selectively maintaining said ring gear of the planetary assembly of higher ratio stationary, whereby the following conditions may be selectively established: a. Neutral position where no operative connecting exists between said variably coupling and the cooperable planetary carrier, and neither the latter or said ring gear of the lower ratio assembly is maintained stationary,   b. Variable-ratio position wherein said fluid coupling is operatively connected to the cooperably planetary carrier and neither the latter or said ring gear of the lower ratio assembly is maintained stationary,   c. Low fixed-ratio position when only said ring gear is maintained stationary and said fluid coupling is connected,   d. Reverse fixed-ratio position when only said cooperable planetary carrier is maintained stationary and said fluid coupling is disconnected.   
     
     
       9. A power train according to claim 8, wherein said respective stationary-maintaining means are constructed for simultaneous operation to maintain both the ring gear unit and said cooperable planetary carrier stationary, thus rendering the driven member stationary. 
     
     
       10. A power train according to claim 8, wherein means is provided acting directly on the driven member for rendering the latter stationary. 
     
     
       11. A power train according to claim 8, wherein said means selectively connecting said planetary carrier and the driving member comprises a fluid coupling having a driving element connectible to said driving member and a driven element connectible to said planetary carrier. 
     
     
       12. A power train according to claim 8, wherein said means selectively connecting said planetary carrier and the driving member comprises a magnetic clutch having a driving element, a driven element and means for effecting a variable coupling between said elements, the driving elements being connected to said driving member and the driven element to said planetary carrier.